﻿#region License
// Copyright (c) Jeremy Skinner (http://www.jeremyskinner.co.uk)
// 
// Licensed under the Apache License, Version 2.0 (the "License"); 
// you may not use this file except in compliance with the License. 
// You may obtain a copy of the License at 
// 
// http://www.apache.org/licenses/LICENSE-2.0 
// 
// Unless required by applicable law or agreed to in writing, software 
// distributed under the License is distributed on an "AS IS" BASIS, 
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
// See the License for the specific language governing permissions and 
// limitations under the License.
// 
// The latest version of this file can be found at http://FluentValidation.codeplex.com
#endregion

namespace FluentDataContract.Internal
{
    using System;
    using System.Collections.Concurrent;

    public sealed class InstanceCache
    {
        private readonly ConcurrentDictionary<Type, object> _cache = new ConcurrentDictionary<Type, object>();

        public bool TryGet(Type type, out object o)
        {
            return _cache.TryGetValue(type, out o);
        }

        public void Add(Type type, object instance)
        {
            object existingInstance;

            if (TryGet(type, out existingInstance))
                return;

            _cache[type] = instance;
        }

        public object GetOrCreateInstance(Type type)
        {
            return GetOrCreateInstance(type, Activator.CreateInstance);
        }

        public object GetOrCreateInstance(Type type, Func<Type, object> factory)
        {
            return _cache.GetOrAdd(type, factory);
        }
    }
}